As a recording medium for recording digital data such as music contents and movie data, various types such as a magnetic disk, an optical disk, and a magneto optical disk exist. Among them, a nonvolatile memory device such as a semiconductor memory card is rapidly spreading since the memory device can be miniaturized mainly in a small portable device, for example, a digital still camera and a mobile phone terminal.
The semiconductor memory card mainly uses a semiconductor element called a NAND type flash memory as a recording element. The NAND type flash memory is required to erase data once prior to writing of data. Since processing of erasing is allowed only in units of blocks called a physical block that is an erasing unit, the NAND type flash memory is characterized in that a speed of the writing will be the fastest in a case of writing in units of the physical blocks. The semiconductor memory card does not always have one NAND type flash memory, and there is the semiconductor memory card improving an access performance by using a plurality of the NAND type flash memories and by processing them in parallel. This semiconductor memory card controls the NAND type flash memory with handling a plurality of the physical block as one management unit, and the writing speed will be the fastest in a case of writing in units of the management units. As described above, a recording speed of the semiconductor memory card changes depending on the size of the physical block of used NAND type flash memory, the number of the flash memories, and a unit size of processing in data writing.
Since the physical block size of used NAND type flash memory for a semiconductor memory card and the number of the used NAND type flash memories are different from manufacturer to manufacturer and from generation to generation, the semiconductor memory cards having various characteristics of the recording speed exist in the market. Conventionally proposed has been a method for accessing all semiconductor memory cards in a high speed regardless of the difference of the characteristics of the recording speed different in each of the semiconductor memory cards by retaining information related to the access performance of the semiconductor memory card in the semiconductor memory card and by transferring and receiving, based on the retained information, information related to the recording speed and an optimum access condition between the memory card and the access device (for example, refer to Patent document 1).
Patent document 1: WO2005/015406